Biocompatible gel to replace damaged cartilage

Washington, Sep 6 (IANS) Experts in mechanics, materials science and tissue engineering at Harvard have created an extremely stretchable biocompatible gel that could replace damaged cartilage in human joints.

Called a hydrogel, because its main ingredient is water, the new material is a hybrid of two weak gels that combine to create something much stronger.

Not only can this new gel stretch to 21 times its original length, but it is also exceptionally tough, self-healing, and biocompatible — a valuable collection of attributes that opens up new opportunities in medicine and tissue engineering.

“Conventional hydrogels are very weak and brittle — imagine a spoon breaking through jelly,” explained lead author Jeong-Yun Sun, postdoctoral fellow at the Harvard School of Engineering and Applied Sciences (SEAS), the journal Nature reports.

“But because they are water-based and biocompatible, people would like to use them for some very challenging applications like artificial cartilage or spinal disks. For a gel to work in those settings, it has to be able to stretch and expand under compression and tension without breaking,” said Jeong-Yun, according to a SEAS statement.

Sun and his co-authors were led by three faculty members from SEAS: Zhigang Suo, professor of mechanics and materials science; Joost J. Vlassak, professor of materials engineering and David J. Mooney, professor of bioengineering.

They combined two common polymers to create the new hydrogel.

“The unusually high stretchability and toughness of this gel, along with recovery, are exciting,” said Jeong-Yun.

“Now that we’ve demonstrated that this is possible, we can use it as a model system for studying the mechanics of hydrogels further, and explore various applications,” added Jeong-Yun.